ALAN Davies and Sarah Alexander cast their spell in a brand new series of Jonathan Creek

Alan Davies has been putting on his trademark duffle coat to play amateur detective Jonathan Creek since 1997 and 17 years later the popularity of the shambling, shaggy-haired sleuth shows no sign of abating.

Alan returns as the eponymous hero this week in a new three-part series in which Jonathan uses the skills he acquired creating magic tricks to unravel more mysteries.

Nearly two decades after he first appeared on our screens, why does this eccentric investigator remain so adored?

“Because he’s so ordinary,” answers actor and comedian Alan, who also appears on panel show QI and recently hosted Alan Davies Après-Ski during the Winter Olympics in Sochi. “Jonathan rolls his eyes all the time – most people do that. He is the archetypal British person who thinks, ‘Why are all the people on TV such idiots?’ Lots of people think like that. Jonathan is a cerebral superhero, but he’s also flawed, feeble, weak and cowardly – actually, he’s not that cowardly! People can really relate to him.”

In the opening episode, The Letters Of Septimus Noone, Jonathan and his new wife, Polly (Sarah Alexander), attend a West End musical based on the classic 19th-century novel, The Mystery Of The Yellow Room.

But life imitates art when the leading lady is the victim of a crime. The star, Juno Pirelli (Ali Bastian), is discovered stabbed inside a locked dressing room from which no attacker could have fled. There is no evidence of a weapon or an intruder.

But Jonathan is reluctant to undertake the investigation. As he and Polly deal with personal tragedy, a string of troubling family secrets are disclosed which turn the couple’s world upside down.

Alan with actress Sarah Alexander as his new wife, Polly [BBC]

When I got the part of Jonathan Creek it was suggested to me that I should read a few books on Houdini, and I became a big fan

Alan Davies

Alan, 47, who will soon tour the UK with his stand-up show, Little Victories, says that in this series Jonathan has finally grown up.

“He is married to Polly, played by Sarah Alexander – which could be worse. I think he’s slightly punching above his weight there,” Alan jokes. “Jonathan’s not in magic any more. He now works in advertising. He thinks it’s absurd, but you can’t live in a windmill making up tricks all your life.”

Working on Jonathan Creek has had other benefits for Alan. Researching the role, the actor became fascinated with legendary illusionist and escapologist Harry Houdini. Now he is presenting a documentary on Houdini for ITV’s new Perspectives series.

“When I got the part of Jonathan Creek it was suggested to me that I should read a few books on Houdini, and I became a big fan,” he says. “Making the documentary, we went to interview magician David Copperfield in Las Vegas. He has his very own private museum. He has an incredible collection of Houdini memorabilia, including an actual water tank from which Houdini escaped.”

There have been hiatuses in the Jonathan Creek series, but Alan is always happy to return to the role because of one man – the show’s creator David Renwick, who was also behind such shows as One Foot In The Grave, Not The Nine O’Clock News and The Two Ronnies.

“The scripts are always fantastic because David writes every single episode himself. His writing is brilliant and he has very high standards. There is no question of him handing the series over to other writers so they can knock out more episodes,” says Alan, who is married with two children.

“David is hugely inventive and has a wonderful ability to structure a story. He understands perfectly what works. David creates shows that people really want to revisit. You’d think they wouldn’t want to watch Jonathan Creek again and again, but they watch it avidly on box sets. These shows are made to last.”